|If you have a designated surface for cutting and use self-healing/rotary cutting mats, there are low profile clamps/fasteners that you can use to hold the mats together so they do not shift.
However, the clamps/fasteners are not easily found. Maybe they have another name???? I bought mine a couple years ago from an Olfa representative at a sewing expo.
Or, you can put a strip of duct tape under the length of the seam where the two mats meet. This works best if the mats do not have to be removed from the work surface.